a Beijing Center for Disease Prevention and Control , Beijing , China.
b Beijing Research Center for Preventive Medicine , Beijing , China.
Hum Vaccin Immunother. 2017 Oct 3;13(10):2379-2384. doi: 10.1080/21645515.2017.1359364.
Influenza vaccination is the most effective way of preventing influenza infections but its coverage is extremely low in China. Poor influenza vaccine effectiveness (VE) was reported in the 2014/15 season in some Northern Hemisphere countries with a predominance of H3N2 viruses belonging to the 3C.2a clade. However, there is limited information regarding the preventive effect of influenza vaccination for the same season in China, in which H3N2 viruses belonging to the 3C.3a clade predominated. Through influenza virological surveillance in Beijing, China during the 2014/15 season, we estimated the influenza VE against medically attended influenza-like illness (ILI) associated with laboratory-confirmed influenza virus infection using a test-negative design, and the effect of prior vaccination on current vaccination was examined. In total, 9297 patients with ILI were enrolled in this study. Among them, 3434 (36.9%) tested positive for influenza viruses: 2167 (63.1%) for A(H3N2), 1261 (36.7%) for influenza B, and 3 (0.1%) for A(H1N1)pdm09. The adjusted VE was estimated as -25% (95% CI: -70%, 8%) against A(H3N2) and -8% (95% CI: -50%, 23%) against B, with an overall VE of -18% (95% CI: -49%, 6%). The overall VE estimate for patients who received 2014/15 vaccination only was -12% (-57%, 20%), while VE for patients who received both 2013/14 and 2014/15 vaccinations was -27% (-72%, 7%). There was no evidence that the influenza vaccine protected vaccinees against medically attended influenza in Beijing, China during the 2014/15 season.
流感疫苗接种是预防流感感染最有效的方法，但在中国的覆盖率极低。在一些北半球国家，2014/15 季节报告了较差的流感疫苗效力（VE），其中优势 H3N2 病毒属于 3C.2a 分支。然而，关于中国同一季节流感疫苗接种的预防效果的信息有限，其中优势 H3N2 病毒属于 3C.3a 分支。通过 2014/15 季节在中国北京进行的流感病毒学监测，我们使用阴性检测设计估计了与实验室确诊的流感病毒感染相关的医疗就诊的流感样疾病（ILI）的流感 VE，并检查了先前接种对当前接种的影响。本研究共纳入 9297 例 ILI 患者。其中，3434 例（36.9%）流感病毒检测呈阳性：2167 例（63.1%）为 A（H3N2），1261 例（36.7%）为 B，3 例（0.1%）为 A（H1N1）pdm09。调整后的 VE 估计为 A（H3N2）为-25%（95%CI：-70%，8%），B 为-8%（95%CI：-50%，23%），总体 VE 为-18%（95%CI：-49%，6%）。仅接受 2014/15 年疫苗接种的患者的总体 VE 估计值为-12%（-57%，20%），而接受 2013/14 年和 2014/15 年疫苗接种的患者的 VE 为-27%（-72%，7%）。没有证据表明流感疫苗在中国北京的 2014/15 季节保护疫苗接种者免受医学上就诊的流感。
